Answer this question truthfully
### Question: What causes Homocystinuria?
### Response: Homocystinuria is inherited in families as an autosomal recessive trait. This means that the child must inherit the non-working gene from both parents to be seriously affected.
Homocystinuria has several features in common with Marfan syndrome. Unlike Marfan syndrome, in which the joints tend to be "loose," in homocystinuria the joints tend to be "tight."